Connector for laboratory tubing



Nov. 2, 1965 J. SCHMID 3,215,456

CONNECTOR FOR LABORATORY TUBING Filed Aug. 7, 1964 INVENTOR.

LEOPOLD J. SCHMID ATTORNEY United States Patent 3,215,456 CONNECTOR FOR LABORATORY TUBKNG Leopold Joseph Schmid, Philadelphia, Pa. Arthur H. Thomas Company, Vine St. at 3rd, Philadelphia, Pa.) Filed Aug. 7, 1964, Ser. No. 388,245 2 Claims. ((11. 285-317) This application is a continuation-in-part of my application Serial Number 97,936 filed March 23, 1961 and now abandoned.

This invention relates to a connector for laboratory tubing, and more particularly, to a novel connector device for use with hollow glass tubes connected together by means of a ground glass joint.

It has been conventional heretofore in chemical and laboratory apparatus, especially vacuum apparatus, to utilize lengths of glass tubing connected together with ground glass joints.

When using hollow glass tubing wherein lengths of tubing are connected together by means of a ground glass joint, it is necessary under certain circumstances to provide an additional means for assuring a positive coupling between the lengths of glass tubing. For example, when working with vacuum apparatus, it is necessary to provide a clamp which engages each length of tubing on opposite sides of the ground glass joint so as to have positive assurance that a leakproof joint will be provided. In a complicated array of glass tubing, it is sometimes necessary to support the glass tubing by means of a stand. The connector clamp of the present invention is adapted to be supported from such a stand if desired. The connector clamp of the present invention is particularly designed for use with straight hollow glass tubing connected together by means of a standard tapered ground glass joint.

It is an object of the present invention to provide a novel connector device for use with hollow glass tubing connected together by means of a ground glass joint.

It is another object of the present invention to provide a novel clamp for use with lengths of hollow glass tubing connected together by means of a tapered ground glassjoint.

It is another object of the present invention to provide a novel clamp for use with hollow glass tubing connected together by means of a ground glass joint wherein the clamp is provided with a locking means which prevents the clamp from being separated from the lengths of glass tubing.

Other objects will appear hereinafter.

For the purpose of illustrating the invention there is shown in the drawings forms which are presently preferred; it being understood, however, that this invention is not limited to the precise arrangements and instrumentalities shown.

FIGURE 1 is a perspective view of a connector clamp in accordance with the present invention.

FIGURE 2 is an elevational View of lengths of tubing connected together by a tapered ground glass joint, partly in section, with the connector clamp of the present invention mounted thereon.

FIGURE 3 is a sectional view taken along the lines 33 in FIGURE 1.

FIGURE 4 is a perspective view of an alternative embodiment of the connector clamp of the present invention.

FIGURE 5 is a sectional view taken along the line 55 in FIGURE 2.

Referring to the drawing in detail, wherein like numerals indicate like elements, there is shown in FIG- URE 1 a connector clamp in accordance with the present invention designated generally as 10.

The connector clamp includes a jaw 12 and a jaw 3,215,456 Patented Nov. 2, 1965 member 14 pivotably connected together intermediate their ends as will be made clear hereinafter. Each of the jaw members 12 and 14 are fiat planar members having an inturned rim at their periphery. That is, jaw member 12 is provided with a rim 16 and jaw member 14 is provided with a rim 18.

The means pivotably securing the jaw members 12 and 14 together includes a pair of ears on each of the jaw members 12 and 14. The jaw member 12 is provided with a pair of ears 20 extending from the rim 16. The ears 29 lie in a plane which coincides with the plane of the rim 16 adjacent thereto. The jaw member 14 is likewise provided with a pair of ears 22. Each of the ears 2% and 22 are provided with a hole therein. A pin 24 extends through the hole in each ear, with the ears 20 being disposed between the ears 22. A torsion spring 25 is disposed around the pin 24 with one end of the torsion spring 25 engaging the inner surface of the jaw member 12 and the other end of the torsion spring 25 engaging the inner surface of the jaw member 14. The spring 25 biases the handle end 26 on the jaw member 12 away from the handle end 28 on the jaw member 14. As a result thereof, the ends of the jaw members 12 and 14 remote from the handle ends 26 and 28 are biased toward each other.

The ends of the jaw members 12 and 14 remote from the handle ends 26 and 28 are provided with a U-shaped recess 30 and 32 respectively. As shown more clearly in FIGURES 1 and 2, an arcuate wall 34 extends from the jaw member 12 around the arcuate portion of the U-shaped recess 30 for an arcuate distance of approximately The arcuate wall 34 has a slight'taper of approximately 5 degrees with the smallest radial dimension of the arcuate wall 34 being remote from the jaw member 12.

The U-shaped recess 30 in the jaw member 12 provides said jaw member 12 with a pair of legs 36 and 38. A gate 40 is pivotably secured to the leg 36 for rotation in the direction of the arrow 42 by means of the screw 44. Screw 44 extends through the leg 36 and is rotatably connected to the gate 40. The end of the gate 40 remote from the leg 36 of the jaw member 12 is provided with a threaded hole. A thumb screw 48 is provided with a threaded stud which is threadingly engaged within said threaded hole in the gate 40. The leg 38 on the jaw member 12 is provided with a U-shaped slot 46. The slot 46 is of sufficient size to receive the threaded stud on the thumb screw 48.

A threaded stud 50 is fixedly secured in any convenient manner to the inner periphery of the jaw member 12, as shown more clearly in FIGURE 2. A nut 52 having a knurled outer peripheral surface is threadingly engaged with the threaded stud 50. The nut 52 is provided with a tubular extension 54 which is provided with internal threads capable of receiving the threaded stud 50. The threaded stud 50 and the nut 52 cooperate perform a locking function as will be made clear hereinafter.

As shown in FIGURE 2, a length of 56 is connected to a length of hollow a tapered ground glass joint. The length of glass tubing 58 is provided with a female tapered section 60' which matingly receives the male tapered section 62 on the length of glass tubing 56.

The free end of the female tapered section 60 is provided with an enlarged bead 64. The large diameter end of the male tapered section 62 is joined with the length of glass tubing 56 in a manner which provides a shoulder 66 at the juncture thereof.

The connector clamp 10 of the present invention is utilized in the following manner:

hollow glass tubing glass tubing 58 by The thumb screw 48 is manipulated so that the gate 40 may be swung to the phantom position shown in FIGURE 1. The handle ends 26 and 28 of the jaw members 12 and 14, respectively, are digitally manipulated by exerting pressure so as to force the handle ends toward each other against the bias of the spring 25. As the handle ends 26 and 28 are moved toward each other, the opposite ends of the jaw members 12 and 14 move away from each other. The connector clamp of the present invention is then moved in a direction substantially perpendicular to the longitudinal axis of the lengths of glass tubing 56 and 58 until the jaw members 12 and 14 assume a position as shown in FIGURE 2. The digital pressure which was being applied against the handle ends 26 and 28 is removed thereby permitting the spring to bias the handle ends 26 and 28 away from each other.

As the handle ends 26 and 28 move in opposite directions away from each other, the end of the arcuate wall 34 abuttingly contacts the shoulder 66 with which the lower edge of wall 34 is parallel while a small flange 68 on the jaw member 14 abuttingly contacts a portion of the bead 64. Flange 68 contacts bead 64 substantially throughout its arcuate length of about 180. The pressure of the spring 25 will be suificient, when using a small clamp, to assure that the ground glass joint between the lengths of tubing 56 and 58 will remain intact and thereby prevent leakage under high vacuum conditions.

When the jaw members 12 and 14 have assumed the position shown in FIGURE 2, the gate will be swung into the solid line position shown in FIGURE 2. Thereafter, the thumb screw 48 will be rotated until firm contact is made with the leg 38. The gate 40 provides a safety feature which prevents the connector clamp 10 from being accidentally separated from the lengths of glass tubing 56 and 58. As shown more clearly in FIGURE 2, the U-shaped recess on the jaw members 12 and 14 is of sufficient size to permit the length of glass tubing 56 to be received within the U-sbaped recess 30 without interfering with the pivotable movement of the gate 40.

With larger size glass tubing, and concurrently larger sized clamps, it is often desirable and necessary to provide a positive means for assuring that the handle ends 26 and 28 will not he accidentally moved toward each other thereby disturbing the seal provided by the ground glass joint. Such means will comprise the threaded stud 50 and the nut 52. When a connector clamp 10 of the present invention has been mounted in the manner shown in FIGURE 2, a nut 52 will be rotated until the end of the extension 54 engages the inner surface of the jaw member 14. There after, it will be impossible for the handle ends 26 and 28 of the jaw members 12 and 14, respectively, to be accidentally or intentionally manipulated in a direction toward each other.

FIGURE 4 discloses an alternative embodiment of the present invention designated generally as 10. The connector clamp 10 is identical with the connector clamp 10 except for the features which will be discussed hereinafter. The elements of the connector clamp 10 which are identical with the corresponding elements in the connector clamp 10 are provided with primed numerals. It is not deemed necessary to explain in detail the function ot the elements of the connector clamp 10' which are identical with corresponding elements in the connector clamp 10.

The connector clamp 10' dilfers from the connector clamp 10 by the provision of a mounting means adapted to mount the connector clamp 10 on a post of a stand. In this manner, the connector clamp not only positively maintains the seal at the ground glass joint, but also is the supporting structure for the lengths of glass tubing. A device of this nature is often desirable Where a com plicated array of glass tubing is being utilized in a laboratory.

The mounting means for the connector clamp 10' includes a pair of side plates 72 and 74 integrally connected together by a crosspiece 73. The ends of the side plates 72 and 74 remote from the crosspiece 73 are provided with aligned apertures. The aligned apertures in the side plates 72 and 74 are in alignment with apertures in the ears extending toward each other from the jaw members 12 and 14'. A pin extends through the aligned apertures in the side plates 72 and 74, and the ears on the jaw members 12' and 14'.

A rod 76 is fixedly secured to the crosspiece 73 and extends therefrom in a direction substantially parallel to the side plates 72 and 74. The end of the rod 76 remote from the crosspiece 73 is provided with any type of conventional clamping structure capable of selectively clamp ing the rod 76 to a post 78 on a stand.

It is believed that the operation and manner of use of the connector clamp 10' is obvious from the above explanation relating to the connector clamp 10. Accordingly, an explanation of the manner and use of the connector clamp 10' is not deemed necessary.

In each of the above embodiments of the connector clamp of the present invention, a spring means is provided for retaining the jaw members clampingly engaged with portions of lengths of ground glass tubing adjacent a tapered ground glass joint. Also, a gate means is provided to assure that the connector clamps cannot he accidentally moved in a direction at an acute angle with respect to the longitudinal axis of the ground glass tubing. Also, the arcuate wall 34 and 34 will prevent the clamp from moving in one direction corresponding to the longitudinal axis of the glass tubing and the flange 68 will prevent the clamp from moving in an opposite direction. Also, an additional locking means is provided for augmenting the biasing eifect of the spring so as to prevent accidental movement of the handle ends of the jaw members toward each other.

The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof and, accordingly, reference should be made to the appended claims, rather than to the foregoing specification as indicating the scope of the invention.

I claim:

1. Apparatus comprising a pair of hollow glass tubes, said tubes being connected by a tapered ground glass joint, said ground glass joint comprising mating male and female elements, a connector clamp for retaining said tubes connected together at said joint, an annular head on said female element, a shoulder on said male element, said clamp comprising first and second jaw members, means pivotably securing said jaw members together, spring means biasing the ends of said jaw members engaged with said tubes towards each other, a U-shaped recess on said jaw members at said ends, an arcuate wall depending from the first jaw member and engaging said male element, said arcuate wall being coextensive with a substantial portion of the U-shaped recess on said jaw member, said arcuate wall being slightly tapered with respect to the longitudinal axis of said tubes with the portion of greatest length being at the arcuate portion of said U-shaped recess, and With the entirety of the circumferential length of the free edge of said wall engaging the shoulder on said male element, said arcuate wall extending in a direction towards the second jaw member, said second jaw member having an arcuate wall which engages the annular bead on the female element, and which extends towards the first jaw member, said jaw members exerting substantially uniform pressure on said male and female elements to clamp the joint together, said free edge of the arcuate wall of the first jaw member, the means pivotably securing the jaw members together, and said shoulder on said male element lying in a single plane, and said jaw members being disposed at substantially the same angle to said plane when in clamping position.

2. A connector clamp for retaining together mating male and female elements of a tapered ground glass joint,

5 said clamp comprising first and second jaw members, means pivotably securing said jaw members together intermediate their ends, said jaw members being intended to engage the male and female elements of the joint for biasing them towards each other, each of said ends of said jaw members having a U-shaped recess, an arcuate wall depending from said first jaw member and terminating in a free edge adapted to engage the male element of the joint, said arcu'ate wall being coextensive with a substantial portion of the U-shaped recess on said first jaw member, said arcuate wall being slightly tapered with respect to the plane of said first jaw member and with the portion of greatest length being at the arcuate portion of said U- shaped recess, said arcuate wall extending in a direction towards the second jaw member, said second jaw member having an arcuate wall coextensive with a substantial portion of its U-shaped recess and extending generally toward said first jaw member, with spring means being constructed and arranged to resiliently urge together said jaw members so as to exert su-bstantially uniform pressure on male and female elements embraced by the U-shaped recesses on said jaw members, said free edge of said first jaw member, said means pivotably securing said jaw members together, lying in a single plane when said clamp operatively embraces male and female elements, with said first and second jaw members being at substantially the same angle to such plane.

References Cited by the Examiner UNITED STATES PATENTS 888,165 5/08 Harrington 285-87 1,328,602 1/20 Steen 24249 1,357,151 10/20 Dalhaus 24-253 1,553,623 9/25 McLeod 81-302 1,916,024 6/33 Simon 29-268 2,397,438 3/46 Schmid 285-420 2,453,669 1 l/ 48 Meneses 285-332 2,691,201 10/54 Matthews 285-420 CARL W. TOMLIN, Primary Examiner. 

1. APPARATUS COMPRISING A PAIR OF HOLLOW GLASS TUBES, SAID TUBES BEING CONNECTED TO A TAPERED GROUND GLASS JOINT, SAID GROUND GLASS JOINT COMPRISING MATING MALE AND FEMALE ELEMENTS, A CONNECTOR CLAMP FOR RETAINING SAID TUBES CONNECTED TOGETHER AT SAID JOINT, AN ANNULAR BEAD ON SAID FEMALE ELEMENT, A SHOULDER ON SAID MALE ELEMENT, SAID CLAMP COMPRISING FIRST AND SECOND JAW MEMBERS, MEANS PIVOTABLY SECURING SAID JAW MEMBERS TOGETHER, SPRING MEANS BIASING THE ENDS OF SAID JAW MEMBERS ENGAGED WITH SAID TUBES TOWARDS EACH OTHER, A U-SHAPED RECESS ON SAID JAW MEMBERS AT SAID ENDS, AN ARCUATE WALL DEPENDING FROM THE FIRST JAW MEMBER AND ENGAGING SAID MALE ELEMENT, SAID ARCUATE WALL BEING COEXTENSIVE WITH A SUBSTANTIAL PORTION OF THE U-SHAPED RECESS ON SAID JAW MEMBER, SAID ARCUATE WALL BEING SLIGHTLY TAPERED WITH RESPECT TO THE LONGITUDINAL AXIS OF SAID TUBES WITH THE PORTION OF GREATEST LENGTH BEING AT THE ARCUATE PORTION OF SAID U-SHAPED RECESS, AND WITH THE ENTIRETY OF THE CIRCUMFERENTIAL LENGTH OF THE FREE EDGE OF SAID WALL ENGAGING THE SHOULDER ON SAID MALE ELEMENT, SAID ARCUATE WALL EXTENDING IN A DIRECTION TOWARDS THE SECOND JAW MEMBER, SAID SECOND JAW MEMBER HAVING AN ARCUATE WALL WHICH ENGAGES THE ANNULAR BEAD ON 